What to do if the program cannot connect to mysql

Solutions for programs that cannot connect to mysql: 1. Determine whether the mysql service is normal, and contact the operation and maintenance to confirm the network problem; 2. Increase the value of “max_allowed_packet”; 3. Increase the value of “net_read_timeout” ; 4. Increase the value of “connect_timeout”, etc. Recommendation: “Mysql Video Tutorial” Summary of the problem that the program cannot connect to mysql When you can’t connect to mysql, there are generally the following four types of errors: 1: Can't connect to MySQL server 2: Lost connection to MySQL server 3: Sorry, due to line fault, temporarily unable to browse, we are dealing with. 4:MySQL server has gone away One: Can’t connect to MySQL server Possible reasons: 1, the mysql server is not started Get up 2, the network is not available (iptables, selinux, network instability) The corresponding solution: 1, the dba first determines whether the mysql service is normal 2, when the mysql service is normal, find the operation and maintenance to confirm the network problem 2: Lost connection to MySQL server There are four situations that may cause this Error: 1, network problem 2, the result set of the query is too large, for example, a query needs to…